Composition for ruby glass.



' UNITED STATES PATENT OFFICE.

RICHARD ZSIGMONDY, OF JENA, GERMANY.

-COMPOS|T|ON FOR RUBY GLASS.

SPECIFICATION forming part of Letters Patent No. 703,512, dated July 1,19 02.

. Application filed December 26-. 1901. derial No. 87,369. (Nospecimens.)

To all whom, it may concern:

Be it known that 1, RICHARD ZSIGMONDY, doctor of philosophy, a subjectof the Emperor of Austria-Hungary, residing at 1 Blumenstrasse, Jena, inthe Grand Duchy of Saxo- Weimar, German Empire, have invented a new anduseful Composition for Ruby Glass, of which the following is aspecification.

The requirements of producing a ruby glass adapted for pressed and blownglasswares are rather great. The glass must be sufiiciently cheap, theprocess of coloring must take place regularly and during the work, andthe color must appear in a sufliciently-pure shade. The process ofcoloring as well as the melting-in must be done without any by-process.

The present invention relates to a composition for ruby glass; and itconsists of mixing barytiferous glass compositions with certainquantities of gold and then melting this mixture in a glass-furnace.gold and of salts of barium ruby glasses can be obtained which becomecolored during the work easily and completely in a brilliant shade, andthe gold is made use of in such a way that its power of coloring isutilized in a most efficient measure. These glasses of baryta possess,with regard to other glasses, the just-mentioned superiorities, it beingsupposed that they do not contain certain impurities that influence theprocess of coloring in an unfavorable manner, and it is also supposedthat unfavorable circumstances of firing-in the furnace on melting-inthe glass do not prevent the after development of the color. Further,theproper proportion between silicic acid and gold is substantial. Theexperiments have shown that not less than 0.25 parts and no more than1.7 parts of gold to ten thousand parts of silicic acid (quartzy sand)must be employed. When. less than 0.25 or more than 1.7 parts of goldare employed, the glass loses the capability of becoming colored redduring the work. On employing more than 1.7 parts of gold an undesirableresult is caused by the precipitation of the gold. The most advantageousresults are obtained with a proportion from 0.6 to 1.4 parts of gold toten thousand parts of silicic acid.

The composition of the glass to which gold By the use of is to be addedcan be varied in difierent ways. For instance, it may be composed ofsilicic acid, alkalies, and baryta only, or other oxids (oroxygen-bearing compounds, as nitrates and carbonates) of bivalent metalsmay be added to or substituted for part of the alkalies or the baryta. Asmall addition of boric acid is allowed, too. However, an addition of anoxid of antimony orof manganese or of iron or of aluminium must beavoided, because such an addition in some cases pre vents thedevelopment of the color. The same disadvantageous eifectis produced bythe addition of a noticeable quantity of lime.

Good results have been obtained with glass compositions containing, asmetallic oxids, Y

soda and baryta only. The baryta may be introduced as oxid of barium,hydrate of barium, carbonate of barium, &c. However, the nitrate is tobe preferred to the other compounds.

As an example of the proportions of mixture with which by the additionof gold a pure ruby glass can be produced the following may be stated:1.66, chemical equivalents, SiO,; 0. 288,0hemical equivalents, Na O;

0.276, chemical equivalents, BaO; or 1.66,

chemical equivalents, SiO 0.41, chemical equivalents, Na O; 0.085,chemical equivalents, BaO.

Also mixtures lying between the abovestated proportions allow theproduction of a good ruby glass. With all these mixtures it is mostadvantageous to use from 0.9 to 0.75 parts of gold to ten thousand partsof silicic acid. The gold may be added to the other components in one ofthe usual forms, as a finely-divided metal or as a metallic compound-forinstance, as chlorid-1' u a solution sufficiently diluted by water.

In order to produce according to the present invention blown articles,it will be preferable at first to cool down the glass'-for instance, byblowing it into a small mold or by of a barytiferous glass compositionto which tains as substantial metallic oxids soda and from 0.25 to 1.7parts of gold are added for baryta, this baryta being added as nitrate,every ten thousand parts of quartzy sand, suband to which from 0.25 to1.7 parts of gold 15 stantially as described. are added for every tenthousand parts of 5 2. A composition for ruby glass consisting quartzysand, substantially as described.

ofabarytiferousglasscomposition which con- In testimony whereof I havesigned my tains as substantial metallic oxids soda and name to thisspecification in the presence of baryta and to which from 0.25 to 1.7parts of two subscribing witnesses. gold are added for every tenthousand parts RICHARD ZSIGMONDY. 10 of quartzy sand, substantially asdescribed. 1 Witnesses:

3. A composition for ruby glass consisting of a barytiferous glasscomposition which con- PAUL RINGER, HANS WEIss.

